Home & DIY calculators
13 free tools
The measuring-tape math behind every weekend project — square footage, paint by the gallon, tile with waste, concrete, mulch, and lumber. Punch in feet and inches and get real numbers to take to the store.
Turn a board's thickness, width, and length into board feet, then a total and an estimated cost.
Estimate how many bricks a wall takes from its length and height, using the bricks-per-square-foot for your brick size, plus a waste allowance.
Size up a slab pour in cubic yards, plus a bag estimate for concrete you mix yourself.
Work out how many deck boards it takes to cover your deck, accounting for board width, the gap between boards, and a waste percentage.
Enter the total area you're covering and your sheet size to get how many drywall boards to buy, with a waste percentage for cuts and breakage.
Turn a room's length and width into the number of flooring boxes to buy, with a waste cushion baked in for cuts and mistakes.
Size up a gravel driveway, path, or base layer — enter the area and depth to get cubic yards to order and a rough weight in tons.
Work out cubic yards of mulch or soil from bed size and depth, plus a count of standard bags.
Work out how many gallons a room needs from wall area, coats, and door-and-window deductions.
Enter a roof's rise and run to get the pitch as x-in-12, the slope angle in degrees, and the rafter length per unit of run.
Measure a room's floor area from length and width, and add multiple rooms to total a whole space.
Turn floor size and tile dimensions into a tile count, with a waste percentage so you don't run short.
Add up your wall dimensions and get the number of wallpaper rolls to order, with an allowance for the pattern repeat and trimming waste.
Frequently asked questions
How much extra should I buy for waste?
For tile and flooring, 10 percent is the usual buffer, bumped to 15 percent for diagonal layouts or a room with lots of cuts. It covers breakage, bad cuts, and keeps a few spares around for future repairs.
Why do concrete and mulch come in cubic yards?
Ready-mix concrete and bulk mulch are both sold by the cubic yard, so that's the number the supplier wants. These tools do the length-times-width-times-depth math and hand back yards, plus a bag count when you'd rather grab bags.
Do these account for doors and windows?
The paint calculator does. It knocks roughly 15 square feet off the wall area for each door or window you enter, so you're not buying paint for space you won't cover.